Nigeria

The Nigerian Centre for Disease Control and UN agencies confirmed that 2 997 cases had been reported in the states of Zamfara, Katsina, Kebbi, Niger and Sokoto in northwest and north-central Nigeria since the disease surfaced in December.

Most victims are between five and 14 years old.

Some 500 000 doses of vaccine have arrived in Zamfara, where the disease surfaced. But officials say two million doses are needed and there's a worldwide shortage. The disease inflames the spinal cord and brain.